'The Blue Boy' incorporates many familiar elements of the traditional ghost
story, from its Christmas setting to its isolated locale and a sense of past
tragedies impinging on the present. Even though nothing supernatural is actually
seen until the finale, it stands out as a ghost story for the finesse with which
it introduces supernatural elements into an otherwise straightforward-seeming
narrative about a couple coping with marital problems and the pressure and
responsibilities of having children.

When Joe breaks off his affair with Beth after his wife Marie falls pregnant
again, Beth refuses to accept this. Already made uneasy by stories about the
'Blue Boy', a child who drowned in the nearby loch, Joe and Marie's relationship
is strained further when Beth forces the revelation of his infidelity. The tone
and style of the main story is extremely matter-of-fact, unlike the 'Blue Boy'
flashbacks that rely on swooping cameras, handheld point-of-view shots, slow
motion, tilted angles etc.

In medical terms, a 'blue baby' is a child born with a hole in its heart, the
discoloration due to cyanosis, a lack of oxygenation of the blood. Here,
however, it's used to describe the drowned boy's exposure to the cold, after
seeing his father being unfaithful with his nurse. Although Joe's similar demise
in the loch is triggered by the appearance of the ghost, intimations of his
death appear from the opening, when Beth's photo of him on the loch is bathed in
a blue mist, then re-emphasised by the accident at the worksite and the
unexplained problem with his cars' brakes.

The thematic importance of the relationship between parents and their
children is given an extra emphasis in the casting, with Emma Thompson's
real-life mother Phyllida Law playing her fictional one. The performance that
really stands out, though, is Eleanor Bron's as the ambiguous Christine, a
religious and superstitious woman whose motives are never made entirely clear.
She doesn't tell Marie the truth about the boy's death and in a brief shot is
seen in the couple's room gazing wistfully at the scan of their baby. Is she
trying to bring the boy back to life, or to provide his unhappy spirit with
closure? The implication at the end, when the scan and a shot of the ghost are
juxtaposed, is that the 'Blue Boy' has been re-born through Marie, suggesting
that Christine's family line hasn't ended after all.